The persona is the invention of Gregg Gethard, 36. Gethard, who got his very early start on the set of PBS's Where In the World Is Carmen San Diego?, is an erstwhile stand-up comedian and journalist. He has been editorializing on Yelp since earlier this year.

Gethard told ABC News that he has long been "mildly obsessed with Yelp," concluding that reviews on the popular site tended to fall into two categories. Either, he said, patrons "trashed" restaurants for a slight "that obviously didn't happen." ("The waiter threw water in my face!" he offered, by way of example.) Or, they left a brand of borderline novelistic assessments that fascinated Gethard.

"I wanted to mess with that a little bit," he explained. "One of the things I liked to do [when I still did stand-up] was come up with characters, so I came up with this sad-sack character that just kind of reveals too much."

Gethard said he knew the idea had promise when his wife endorsed the scheme. By his own admission, the reviews are not his first attempt at a "kind of weird, social experiment."

"My wife usually hates this stuff, but she really liked this one," he said. He declared it "a sign" to continue the project, "because she has the best taste of anyone I know."

The hero of Gethard's imagination has composed only five-star reviews for such establishments as the Grape Room, LA Fitness, and Falls Flowers. In the process, he has chronicled the dissolution of his marriage to ex-wife Cynthia, skirmishes between his children, Bradley and Bryan ("B'n'B"), and a brief relationship with "lady friend" Tonya M., who is "trying to repair her own life after recently being released from an 18-month prison term for committing voter fraud."

In a characteristic summary of a meal at The Nile Cafe in April, Gethard-as-Karl G. wrote:

"I have to say that the food was definitely unique. And by that I mean DELICIOUS. Everything was so tasty -- the okra, faux BBQ chicken, vegetable platter, etc. I'm very glad I tried it out. ...I would recommend Nile Cafe to anyone in Northwest Philadelphia who is contemplating veganism as a means to help them try new things as a means of self-improvement when dealing with the collapse of a 14-year marriage."

As is so often true of Internet confessionals, Karl's dispatches are at once uncomfortable, revealing, and engrossing.

"I have the narrative mapped out and Karl's tale will end soon," he said. "I don't want to give away the ending, but...[i]t's going to have a happy ending. After that, Gethard said he hopes to embody a new character, albeit one with whom Karl is very familiar.

"I think it's going to be Cynthia, the ex-wife," he said. "That's who I'm leaning towards. I've got to work on that, but I'm definitely going to keep going."

Ideally, Gethard said he'd like to "weave a weird kind of Yelp-ish Springfield" of the varied narrative threads.

But no matter which character he next articulates, Gethard said he plans to remain resolutely positive online.

"I think it makes the character more likeable," he said. "He's going through something a lot of people go through with a divorce. The reviews he does of these places are enthusiastic, [because] that gives a little bit of a subtext to him wanting to try new things. I like that about him."

Ultimately, Gethard would love to see his protagonist live on...off the web. But he's content to tell a virtual story for now.

While Yelp may not be an obvious platform for that message, Gethard has found it to be an unexpected fit: "I definitely believe that going out to new restaurants and really embracing [the act of] trying new things--even if it's just a type of food you've never had before--is a good way to show that you're trying to change and grow yourself."

"I don't want to sound...pretentious," he hastened, "But I want to make this a redemption story. ...As ridiculous as this is, it is about a guy, you know, realizing what he did wrong with his life. He's realized how his marriage came to an end. He's struggling as a father. He puts too much of himself in his career. I'm 36 years old. I know a lot of people who can relate to that. The idea is, you know, you can change."

Besides, he added, "This whole thing is a pretty easy way to entertain yourself."